Valor Equity Partners has ended its investment in Uptake Technologies three months after putting $35 million into the data analytics startup, according to a letter the Chicago private equity firm sent to investors this week.

The Nov. 22 exit came shortly after Caterpillar, which took an early minority stake in Uptake, ended its role as an investor in Groupon co-founder Brad Keywell’s startup.

“While we continue to believe in Uptake’s long-term vision and disruptive potential, material developments since our initial debt security underwriting fundamentally changed our perception of the risk equation for this investment,” said Antonio Gracias, Valor’s founder, in a Monday letter to investors, a copy of which was obtained by the Tribune.

The Tribune reported Nov. 15 that Caterpillar was ending its investment in Uptake but would remain a customer.

Last week, Uptake announced that it raised $117 million in its latest round of funding, led by U.K.-based investment management firm Baillie Gifford. Existing Uptake investors Revolution Growth, a Washington, D.C.-based venture capital firm headed by AOL founder Steve Case, and Chicago-based GreatPoint Ventures also participated in the funding round.

Uptake Chief Financial Officer Michael Bruns said Tuesday the company raised convertible debt from Valor and other investors so it would have funds to redeem its equity from Caterpillar. “There were a number of restrictions we had in working with Caterpillar, and we were able to eliminate all of those and open up a number of new markets for us to attack independently,” Bruns said of redeeming Caterpillar’s shares.

Valor made the $35 million investment in Uptake in August, according to the letter to investors. It had an option to convert its note into equity or have it repaid when Uptake raised its next equity financing round. Gracias told investors the Valor fund received $36.2 million in cash from Uptake.

Nancy Kowalczyk, general counsel at Valor, and Uptake spokeswoman Abby Hunt declined to comment on the reason for Valor’s exit. Gracias declined to talk to a Tribune reporter.

Valor was founded in 1995 and focuses on high-growth companies. Its other investments have included Elon Musk’s SpaceX and Tesla Motors, Northbrook-based Marathon Pharmaceuticals, and office lunch startup Fooda, among others.

Uptake, formed three years ago, has expanded to analyze industrial data in 10 fields, including agriculture, aviation, mining and energy. As a result of an investment earlier this year, Uptake became a unicorn, placing it among the few Chicago tech startups valued at $1 billion or more. Including the funding round announced last week, Uptake has raised $263 million overall, according to research firm Crunchbase.

Uptake employs about 800 people, most of whom are at its headquarters in the Goose Island neighborhood, Hunt said.